This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We hypothesize that the integrity of executive functions (EFs) is crucial to the development of discourse processing, academic achievement, and adaptive behavior while inhibition and metacognitive skills are related to the psychiatric outcome of CHI in children. Aim 1 addresses the relationship of specific EF deficits involving working memory, inhibition, and metacognitive skills to the acute severity of CHI, imaging of focal brain lesions, and age differences. Aims 2 and 3 represent a new direction which investigates how variability in the integrity of working memory, inhibition, and metacognitive skills is related to discourse, academic achievement, adaptive behavior, and psychiatric outcomes of CHI in children. Specific hypotheses include the following: 1. Aim 1: Impaired development of working memory, inhibition, and metacognitive skills is directly related to the severity of acute CHI and the volume of residual prefrontal lesions. Development of working memory, inhibition, and metacognitive skills is more adversely affected by severe CHI occurring before age 9 years as compared to the outcome of severe CHI occurring in older children. 2. Aim 2: Problems in discourse processing, scholastic achievement, and adaptive skills are directly related to deficient development of working memory, inhibition, and metacognitive skills following head injury in children. 3. Aim 3: Children whose inhibition and metacognitive skills are impaired following CHI are at increased risk for developing attention-deficit/hyperactivity disorder (ADHD), and related externalizing disorders (i.e., Oppositional-Defiant and Conduct Disorders). Posttraumatic internalizing disorders are related to preinjury internalizing disorders and the psychological stress associated with the injury. The presence of prefrontal and/or basotemporal lesions, history of a preinjury psychiatric disorder in the child or parents, and adverse psychosocial environment contribute to the increased risk of developing a psychiatric disorder following CHI. This project integrates cognitive constructs with brain imaging and outcome domains which include developmental neuropsychiatry with the goal of improving assessment and interventions for brain injured children. The goals of the proposed research are: (1) to elucidate impairments of fundamental cognitive processes, including working memory, inhibition, and metacognitive skills in relation to the severity of closed head injury (CHI) defined by the Glasgow Coma Scale, focal brain lesions depicted by magnetic resonance imaging, and age at injury;(2) to evaluate the impact of deficits in working memory, inhibition, and metacognitive skills on outcome domains, including discourse processing, academic achievement, and adaptive behavior;and, (3) to examine the effects of posttraumatic impairments of inhibition and metacognitive skills, CHI severity, and focal brain lesions on the development of new psychiatric disorder, and assess the role of family environment, preinjury psychiatric history, and psychological stress as effect modifiers.